Dropped Valve............... Really

[steve32c]

What would be the initial symptoms of a dropped valve? and would it stop the car with the same symptoms of a cam belt snap / coming off. Dealer has now had the car for over three weeks. After a Cam belt change the car wasn't picking up or accelerating as quick as it should have, there was also a slight ticking from the front end under acceleration and occasionally changing from 4th to 5th gear around the 3K rev area the car would hesitate for a few seconds which seemed an age, with a fluttering sort of sound form the front then suddenly pick up again.
After nearly four weeks dealer says its a dropped valve and that the engine will have to be replaced as it might have damaged the crank shaft.

 

[Thrill]

Dont use dealers!

 

[The Chubby Pirate]

Let them replace it?

 

[Fletcher]

Are you still running 421s with a ktec map?

 

[Laine_16v]

A dropped valve will stop you in your tracks immediately in a cloud of rattling smoke, and will probably lock the engine up. its not a progressive failure like you describe.

 

[Silent_Scone]

As above, it just happens. There is never really any tell tale sign. Think of a giant penny smacking around inside your engine like an impact hammer. Gameover

 

[Ph1 Tom]

Depends on the severity, if the head has come off the valve it'll be a right mess and a new engine job.

If the valve just isn't opening and closing properly (broken valve spring for example) then a replacement valve and spring is required. It'll have a missfire as one cylinder won't be making compression.

 

[Cub.]

Are you still running 421s with a ktec map?

Who did the belt considering the above?

 

[steve32c]

Are you still running 421s with a ktec map?

It is or should I say was

 

[steve32c]

Who did the belt considering the above?

Renault main Dealer, havin checked with K-tec the dealer should have seen they weren't original Cams

 

[steve32c]

Now looking for a cheap replacement until November as they can poke £3200 for a new engine

 

[MartinR]

Renault main Dealer, havin checked with K-tec the dealer should have seen they weren't original Cams

So if 421's are dialled in with standard timing positions this can be the aftermath??

Are the ends of 421 cams different to that of standard ones?? How would renault know the difference? They can't tell between coolant and screen wash...

Hope you get it sorted.

 

[steve32c]

Not sure more probably different markings

 

[BoatNonce]

It's not a very good idea to let a dealer loose on a modified engine, if you're lucky they might be able to do it properly with a standard one. A modded engine is likely to be alien to them.

Mixing K-tec and dealers is like b**ch-slapping a grizzly bear.

 

[ND04]

I would get DTM to check it over speak to Andy.

 

[Cup_Phil]

The cams should run fine on standard timing.
A dropped valve wouldn't damage a crank shaft (lol)

Dealer doesn't know arse from elbow.

 

[Dan@SJM]

421's are timed up as normal. You can't really tell from the end of the cams if they're oem or aftermarket (unless your looking specifically to see if they are or not)

 

[Dan519]

the symptoms you've described are not that of a dropped valve. sounds like they're just botched the timing (probably got the pin in the wrong place on the crank) and don't know how to fix it.
​

 

[scott.p]

Doesn't sound like a dropped valve. When mine dropped a valve the car ground itself to a halt in a cloud of steam out of the exhaust.

 

[steve32c]

cloud of crap out the back out but still progressed up the road in gear, gliding to a stop in a handy layby a 100 yards up the road, smell of hot rubber from the engine bay - but the belt is intact according to the dealer.
Sent off a complaint to RUK as not too impressed with the way things have gone on see what comes back.
Now looking at a cheap runabout for a couple of months as well as getting the best quote for scrap £250 so far............

 

[DTM Cars Ltd]

Really hope you get to the bottom of this.

What a shame.

Remember when its sorted the only stop locally you need to come to is DTM

 

[Dan@SJM]

If give £500 for it.

 

[lemonnobby]

Sounds like timing has slipped to me.
and there trying to get out of it.
see if someone local can go to dealer with you to inspect it.

 

[steve32c]

Really hope you get to the bottom of this.

What a shame.

Remember when its sorted the only stop locally you need to come to is DTM

Hope you get up to speed on the 200t as it won't be going near them - thankfully no cam belt just a chain, which makes a bigger mess if it goes..........

 

[steve32c]

If give £500 for it.

If you can collect it, I'll keep you in mind depending on final outcome......... fingers crossed.

 

[mi16chris]

So if 421's are dialled in with standard timing positions this can be the aftermath??

Are the ends of 421 cams different to that of standard ones?? How would renault know the difference? They can't tell between coolant and screen wash...

Hope you get it sorted.

i just fitted my 421s at the weekend on stock setting , no problem at all and it made 210hp tonight so its nothing to do with the cam timing if they set it as it should have been

 

[steve32c]

Having been to see the car took a few snaps, here are a few photos of the damage

And to add insult to injury cracked the front grill by leaning on it with the slam panel removed.

 

[Dan519]

I will never understand people that dismantle engines without moving things from around them, it's asking for damage! God knows how the aux belt can go on and off without the AC pipe being unbolted from the front panel